Glaucoma is the second most common cause of irreversible blindness after macular degeneration and affects about 3 million Americans. Less than half of those affected know that they have glaucoma and even of those treated, about 10% will still lose their vision as a result of this disease. About 12% of all cases of blindness in the Unites States are due to glaucoma.
How To Spot Glaucoma
One of the obstacles with early diagnosis of glaucoma is that the most common type is not easy to spot without tests. In fact in the early stages a person may have no signs or symptoms. Even as the condition progresses, the onset of the symptoms are so gradual that a person may not notice it. Without diagnostic investigation, most people will not know that they have glaucoma until the advanced stage. Therefore routine screening is important, especially for high risk individuals.
However, the less common types of glaucoma present with several intense signs and symptoms. It can sometimes be mistaken for other eye conditions to a person without adequate knowledge about the signs and symptoms of glaucoma. Given how common glaucoma has become especially in older people and the severity of complications, it is important that every person is familiar with the presentation of glaucoma. People at risk should be particularly aware of these symptoms and seek immediate medical attention if these symptoms do arise.
Read more about glaucoma.
What happens in glaucoma?
Glaucoma is one of several conditions of the eye that can lead to blindness. It is a group of disorders where the optic nerve at the back of the eye becomes damaged. This is usually associated with increased pressure within the eyeball (intraocular pressure or IOP) which occurs in most types of glaucoma. However, there are types of glaucoma where the pressure within the eyeball is normal yet the optic nerve becomes damaged.
Normally the watery fluid in the front part of the eyeball known as the aqeous humor is constantly secreted and drained. In glaucoma, this drainage is impaired in some ways so the fluid builds up thereby increasing the pressure within the eye. It can also occur with overproduction of this fluid where the excess cannot be adequately drained out. There are different types of glaucoma, including:
- Primary open-angle glaucoma which is the most common type of glaucoma. It accounts for 90% of cases, develops gradually and is usually asymptomatic until the late stage.
- Angle-closure glaucoma is a less common type of glaucoma. It arises suddenly with severe symptoms that are noticeable almost immediately.
- Normal tension glaucoma is another less common type where the eyeball pressure is not raised as is the case with primary open-angle and angle closure glaucoma.
- Congenital glaucoma is a type of glaucoma that is present from birth usually due to some abnormality in eye development. It is a rare type of glaucoma.
There are several other types of glaucoma, such as traumatic glaucoma which arises with injury to the eye. However, these glaucomas are uncommon with primary open-angle glaucoma accounting for 90% of all cases.
Who gets glaucoma?
Glaucoma can affect any person, even children. However, it is older people (over the age of 60 years) who are at a greater risk. The following factors are increase the risk of developing glaucoma and these individuals need to consult with an opthamologist regularly for routine screening.
- Family history of glaucoma,
- History of high blood pressure, heart disease or diabetes.
- Eye injury.
- Eye surgery.
- Removal of both ovaries early in life (before age of 43 years).
- Long term use of corticosteroids, particularly eyedrops.
Do not wait for symptoms like diminishing or distorted vision or any of the other signs and symptoms discussed below. People who are at risk should have a routine eye examination every year or two, depending on the recommendation of a medical professional. Without early diagnosis and prompt treatment, glaucoma can lead to blindness. This type of blindness is irreversible.
Read more about glaucoma tests.
Eye Pain and Headache
Eye pain is characteristic of an acute angle-closure glaucoma, which is the less common form of glaucoma. It often arises suddenly and is accompanied by a severe headache. An attack is usually triggered by activities such as watching a movie in a theater, using cold medication or when the pupils are dilated for eye examination. There may sometimes be intermittent episodes with mild pain and little visual disturbance before a full blow attack occurs.
With open-angle glaucoma, the more common type, there is patchy vision and usually this is in both eyes. This may affect the central or peripheral vision. In the advanced stages of this type of glaucoma there may tunnel vision in the advanced stage of the disease. This develops gradually. With the less common type, angle-closure glaucoma, there are reports of blurred vision and halos around lights. It tends to arise suddenly.
Redness of the eyes are also seen with acute attacks of angle-closure glaucoma. It occurs along with eye pain, headache, visual disturbances like blurring and sometimes nausea and vomiting. Due to a lack of knowledge, symptoms like eye redness and eye pain are mistaken for eyestrain, conjunctivitis or other common eye conditions. Without prompt treatment it can lead to blindness.
Nausea and Vomiting
Nausea and vomiting usually occur with attacks of angle-closure glaucoma. There are visual disturbances, eye redness and pain as well a headache which occur together with the nausea and vomiting. Sometimes this nausea and vomiting is mistaken for other conditions as it is relatively non-specific. If all these symptoms occur after a head injury then it needs to be investigated immediately.
Signs of Glaucoma in Babies and Children
Although congenital glaucoma is uncommon, it is important to know the signs of this disease as infants cannot report symptoms. Congenital glaucoma presents with excessive tearing, light sensitivity and a cloudy enlarged cornea. The iris (part responsible for eye color) may also appear dull. Juvenile glaucoma, which is different from congenital glaucoma, occurs in children. It is often associated with a family history of glaucoma and there are few or no symptoms similar to adult glaucoma.